Richard Mortensen (1910–1993) was a Danish painter.

Influenced by the works of Wassily Kandinsky, he developed an abstract art style. In Copenhagen, Mortensen was joint founder of the "Linien" school of abstract painters.

In 1947 moved to Paris remaining there until 1964. Together with Robert Jacobsen, Mortensen became connected to the Galerie Denise René in Paris, which became famous for concrete art. His later works are concrete works of art characterised by large, clear, bright colour surfaces.